Continuous rotary forging die



' April 1 3, 1937. T. A. BOWERS CONTINUOUS ROTARY FORGING DIS 2 Sheets-Sheet 1 Filed May 13, 1935 .April 13,1937. T. A. BOWERS 2,076,541

CONTINUOUS ROTARY FORGING DIE Filed May 15, 1935 2 Sheets-Sheet 2 five M d-QM I iza'rfla y Patented Apr. 13,1937

UNITED STATES PATENT OFFICE 2,076,541 CONTINUOUS ROT-ARY rename on:

Thomas A. Bowers, Boston,

Mass., assignor to Flexion, Inc., Boston, Mass, a corporation of Massachusetts Application May 13,1935, Serial No. 21,183

3 Claims.

\ pending application, for Piston ring and piston ring material, Serial Number 733,243, filed June 30, 1934.

In my present invention, I have developed a new method of forming a metal ribbon piston ring material which briefly comprises the intermeshing of a plurality of forging dies mounted on, or comprising, the peripheries of a pair of discs. The forging dies of respective discs are adapted to mesh together with the material interposed therebetween and constitute'a continuous rotating die. The actual forging of the material, in either a cold or heated state, takes place at, or near, the dead center lineof -the pivot points of the two discs. I have also incorporated certain other features in combination :with the forging discs for the. purpose of stripping the forged material from the forging dies of the discs. Such stripping mechanism is more adaptable for the particular material shown in the drawings and while such stripping mechanism forms a part of the present application and is so claimed yet I may use the same method of forging with different dies and with material of the same or a different character with which no stripping mechanism would be necessary.

The principal object of my invention is therefore an improved method of forming a piston ring material.

Another object is an improved method of forging.

Another object is an improved method of forging a metal ribbon through the medium of oppositely disposed rotating dies.

Still another object is an improved method of forming ametal ribbon for piston ring material by forging the metal ribbon with crowns and webs.

And still another object is an improved method of stripping a forged material from the forging dies. g

Another object is an improved apparatus for formng reversely bent piston ring material.

bends I l.

metal ribbon used in the manufacture of my improved piston ring. V

Fig. 2 is a similar piece of material after having been crimped preparatory to being forged.

Fig. 3 is a side elevation of a fragment of a 5 pair of rotary forging dies and stripper mechanism with the material, shown in Fig. 2, entering at the left side of the dies and emerging in its forged condition from the right side of the dies and having a path of motion indicated by the arrow at the right hand side of Fig. 3.

Fig. 4 is a plan cross section taken on the line 4-4 of Fig. 3 showing the central part of the stripping mechanism in plan with the top forging dies removed.

Fig. 5 is another cross section taken through the stripping mechanism and forging discs and indicated on the line 55 of Fig. 3 and Fig. 6 is a modification of another stripping means with the forging dies illustrated at the left of the figure and being identical with those shown in dotted lines in Fig. 3.

Referring more in detail to the drawings, Ill indicates a strip of metal ribbon which has been passed through a preliminary step for the purpose of forming a plurality of oppositely opposed The reversely bent material III is entered between the dies I2 and I3 of the respective discs I I-and I5 more clearly shown at the left hand side of Fig. 6. A pair of guide blocks I6 and I1 comprising a part of the aforesaid stripping mechanism are mounted on a base, not shown, at opposite sides of the discs I I and I5 adjacent the pitch line of the discs and adjacent the points at which the dies I2 and I3 engage material II.

In Fig. 5 it will be noted that the guide blocks I6 and II are provided with slots I8 which extend in a horizontal manner throughout. These slots I8 have a vertical height, as viewed in Fig. 5, of

exactly the same distance as the space provided between the bottom of die I2 and the bottom of die I3 which corresponds to the total vertical height of the forged material2II. Also' theslots I8 are adapted to receive pairs of shoe members 2| and 22. These shoes particularly the first pair, indicated at 2|, are adapted to receive thebent material II and guide it in alignment with the 'dies I2 and I3 up to the point at which forging takes place which is at the center line between the. discs I4 and I5 and is indicated in Fig. 4 at the point 23 also being the rear end of the shoes 2|. Shoes U are adjustably secured in the block members I6 and II by means of pins 24 embedded in the top and bottom sides of blocks I6 and I I provided in the block members It and I1 respectively for the purpose of maintaining and aligning the material H) in any desired position and also for the purpose of providing any desired friction against the shoes 2|. Set screws 28 are provided in the blocks l6 and for the purpose of increasing or decreasing pressure of the shoes 2| against the sides of the material Hi. It will be noted by inspection of Fig. 4 that the shoes 22 in the rear of the blocks l6 and H are somewhat narrower, as viewed therein, than the shoes 2| and the forged material 20 is wider than the material II]. It is of course apparent that the shoes 2| and 22 can be of exactly the same width and the space between occupied by the forged material 20 may be wider than the space and material between shoes 2| by simply adjusting springs 26 and 26a and set screws 28 and 28a, it being immaterial which means is employed.

As the material I0 passes under the dies l2 and I3 at the center line bf the discs, the pressure of the dies reaches its maximum point and the material I0 is pressed into the spaces 29 between the dies I2 and I3 forming a flat top 30 hereinafter collectively indicated as crowns on the material 20. That portion of the material l0 located between the crowns 30 of the forged material 20, and hereinafter designated as webs 3|, has become materially thinned with a part of the displaced material or metal being flattened out and expanded outwardly against the shoes 22. shoes 22 are fixed in the block it and H in the same manner as the shoes 2| having elongated slots 25a throughwhich pins 24a are located.

In Fig. 5, the material 20 has been cut in cross section at a point close to one of the lower crowns 30 with the material 20 being severed angularly across one of the webs 3 I. It will be noted in this figure that the horizontal width of the web 3| as viewed in Fig. 5 extends together with the crown 30 to a point beyond the edges ofthe dies 2 and I3 and is received against the inner edges of shoes 22. Therefore, as the material 20 passes out from engagement in the dies, I2 and I3, the crowns 30 and the webs 3| are stripped away from the dies I2 and I3 and continue out through the blocks 6 and I! in a horizontal direction, thereby eliminating any sticking of the material 20 in the dies l2 and I3. At the same time, shoes 22 against which the forged material 20 has been tightly pressed produces a smooth edge to the sides of crowns and webs 30 and 3| respectively. In Fig. 6, I have shown a modification of a stripping means comprising a pair of discs 32 and 33 havmg similar dies l2 and I3- formed on, or comprising, their peripheries and adapted to loosely mesh with the material 20. The dies 2 and I3 may-or may not be exactly shaped like the correspondingopen points of the material 20 and may be more or less rounded like gear teeth. The object of these discs 32 and 33 isthe maintaining of engagement with the forged material '20 and the production of a light tension-on such material between the discs 32 and 33 and the forging dies |2 and I3. ,1

The,

To accomplish this result, I provide another pair of discs 32 and 33 having one tooth more than on discs l4 and I5 and having the same revolutionsper minute. When lining up the material in the machine, tension on such material may be obtained between the gears l4 and I5 and the discs 32 and 33 placing a slight tension on the material 20 at the right hand end so as to advance such material to the extent of one tooth between the two sets of discs and stripping the said material 2|! from the, forging dies l2 and |3 of the discs Hi and I5.

A final point is pointed out with respect to the forming of the thinned web construction. It will be noted that when tooth portion I2 is on dead center over the female die portion 29, the space between oppositely occurring sides of the teeth l2 and I3 is less than the normal thickness of the ribbon material to the effect that a thinned web construction results from passage of the ribbon material therethrough and the metal is extruded into the crowns.

It will be apparent that although I have disclosed a method of forming a piston ring material by rotary forging, I might employ the same method of forging on various kinds of material for other purposes such as embossing and the like in a continuous rotating die operation, therefore, I have directed claims to a method of forging as well as to a method of forming by forging a piston ring material and it is to be understood that I may change the design and substitute differently shaped dies on the discs l3 and M or I may make the dies interchangeable on such discs without departing from the spirit of the invention.

Having thus described my invention, what I claim is:

1. A mechanism for producing piston ringmaterial comprising a pair of complementary rotating dies adapted to form a metal ribbon into crowns and connecting web portions, blocks located adjacent either side of the engaging faces 'of said dies, longitudinally disposed grooves in said blocks adapted to engage the extremities of said crowns and webs. I

2. A machine for. producing piston ring material havingtcrown and web portions formed from a metal ribbon comprising a pair of discs located one above the other, complementary die members mounted on the peripheries of said discs and adapted to engage the material therebetween, guide block members located at the sides of said discs, said blocks having channels longitudinally disposed therein, shoe members slidably recessed in said channels, means for transversely adjusting the pressure of said shoe members against the material.

3. A mechanism for producing a piston ring material from metalribbon comprising a pair of complementary dies adapted to form the said ribbon into crowns and connecting web portions, blocks located adjacent either side of said dies, longitudinally disposed grooves in said blocks adapted to engage the extremities of said crowns and webs and shoe members recessed in said blocks ina laterally adjustable manner.

THOMAS A. BOWERS. 

